KerimF
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It would be easier if your spec delay time were longer. Pico-seconds are difficult to work with.
There are ways to arrange a diode-capacitor-resistor so as to turn incoming square waves into an assortment of different wave shapes...
Upward ramp, downward ramp, sudden drop or rise, plateau or mountain-peak...
You might experiment with these configurations and obtain a waveform you can work with. Then apply Vctrl to level-shift. Then feed it to a Schmitt trigger. Output is a delayed pulse.
It seems that this solution is good if integrated. So I wonder if it is also practical to apply it in the special case which I mentioned on post #4 (using standard ICs and discrete components).Many ways to make a variable delay, e.g. this one https://www.edaboard.com/threads/current-starved-inverter-as-delay-element.406154/
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This seems a practical solution. But it needs a close study of its non-linearity perhaps, besides its interfacing at its input (a CMOS output of a flip-flop) and at its output (an input control pin of a CD4066 switch).A CMOS inverter with variable supply voltage can also do the trick.
It seems that this solution is good if integrated. So I wonder if it is also practical to apply it in the special case which I mentioned on post #4 (using standard ICs and discrete components).
There are SPICE vendor models of CMOS gates, e.g. from Nexperia.
Hi,
Standard IC? What is a standard IC?
Standard LOGIC ICs? I don´t know any that are able to produce a delay as small as 150ps.
You mentioned them, so did you do a research about delay times of standard ICs?
Klaus
Hi,
I still don´t understand. In post#4 you also talk about frequencies below 1MHz.
This means more than 1us = 1,000ns = 1,000,000 ps.
The CD4066 datasheet talks about delay of typ 20ns up to 40ns (@10V). You see there are several ns of uncertainty.
20ns equals to 20,000ps.
But you talk aboutthe delay of 150ps to 350ps ... which is way overruled by the uncertainty of an CD4066.
I don´t understand how all these numbers fit.
Klaus
Hi,
I understand the 275ns
But then you talk about a 10k, 100nF combination which is about 4000 times that much in delay.
You're not close at the same area.
Klaus
At the speed of light, 250 pSec delay is a fraction of an inch. Theoretically you can touch two wires together at different points along their length, to obtain any range of delays.
Or turn on any of a series of transmission gates at points along a wire, to obtain the delay.
Since you mention using a 4066 IC, here's a CMOS transmission gate found in Falstad's simulator circuit library. The control wire is interactive user switchable (Hi or Lo) during a run.
As you say, changing the wire length doesn't offer an easy method to vary the delay.I can't see the DC controlling voltage by which a delay could be varied from about 150ns to 350ns.
n order to do it electronically and rapidly It may be necessary to invent a new component. Or a novel usage of components.
At least for me.May I say that the purpose of this thread reached its end?
I´m so confused. Every post gives new - to me random - informations.
Picoseconds, nanoseconds, picofarads, nanofarads ... I don´t know what is valid now.
Now in post#17 you talk about a "triangular signal" ... where does this come form. Never mentioned before..
And how do you want to "shift it with a resistor"?
And how can it "change the duty cycle of the square wave"? The only "square wave signal" in the above posts is the input
The new main circuit here is the DSB-SC modulator (assumed non-existent universally)
It seems you didn't notice yet
So as long you will not have time to have a good idea
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